With the recent surge in popularity of digital video, the demand for video compression has increased dramatically. Video compression reduces the number of bits required to store and transmit digital media. Video data contains spatial and temporal redundancy, and these spatial and temporal similarities can be encoded by registering differences within a frame (spatial) and between frames (temporal). The hardware or software that performs compression is called a codec (coder/decoder). The codec is a device or software capable of performing encoding and decoding on a digital signal. As data-intensive digital video applications have become ubiquitous, so has the need for more efficient ways to encode signals. Thus, video compression has now become a central component in storage and communication technology.
Unfortunately, conventional video compression schemes suffer from a number of inefficiencies, which manifest in the form of slow data communication speeds, large storage requirements, and disturbing perceptual effects. These impediments can impose serious problems to a variety of users who need to manipulate video data easily, efficiently, while retaining quality, which is particularly important in light of the innate sensitivity people have to some forms of visual information.
In video compression, a number of critical factors are typically considered including: video quality and the bit rate, the computational complexity of the encoding and decoding algorithms, robustness to data losses and errors, and latency. As an increasing amount of video data surges across the Internet, not just to computers but also televisions, cell phones and other handheld devices, a technology that could significantly relieve congestion or improve quality represents a significant breakthrough.